I'm less than satisfied with the Focusrite 2i2. When its looped back (cabled) i get a respectable 0.0007 THD and 0.002 THD+N (from memory). Problem is as soon as you just use the outputs into other equipment its noisy, like real noisy. This is confirmed with a scope. Its not earth loops or anything like that.. its white noise. In fairness to Focusrite they do focus on the mic inputs and it is a gen 1.
What parts of the output does the loopback measurement use?
I can imagine a bad joint on the ground connection of the output which is not required for the loopback (as the input and output grounds are already connected within the soundcard).
I can imagine a bad joint on the ground connection of the output which is not required for the loopback (as the input and output grounds are already connected within the soundcard).
Its a cabled loop back so all analogue parts used. It is odd why it measures well in this state but performs bad with other equipment. As I say its not earth loops as laptop is running on batteries and scope is isolated. I might set it all up and post screen shots.
I am not talking about a ground loop, but about the ground wire. No ground wire is required for a loopback (input and output share the same ground), but a proper return path is required for an external equipment. There must be a reason and I guess it will be something simple.
Thanks for the feedback phofman but I think I'd pick up a "one leg dis". My personal experience is this may be a great mic preamp as intended by Focusrite but is not a great contender for DUT THD measurement.
Please do, as the odds are that you have a poor measurement set up. Perhaps provide a few independant measurements of the noise.
Why not start with PK's measurements? I only saw those last night after ditching the 2i2 a year or so ago.
Many interfaces have level ranges where noise and distortion are quite good, and outside of the region then performance degrades. A few have posted here with a woeful result, only to then spend some time to work through those level issues. Without a good range of results and levels, it is suspect that your experience, or a simple table of results, is a fair assessment.
Thanks trobbins. Yes I'm familiar with what needs to be done. I had an EMU 0204 and achieved reliable PPM results testing real world power amps. Unfortunately it packed up. Moved to the focusrite, not satisfied. Anyhow I have a Motu turning up so hopefully that will be an improvement on the EMU. Not investing any more time in the 2i2. I note you are in Melbourne. wanna buy it? 🙂
I got a very cheap ebay USB 0404 back in 2014, and so far it meets all my needs (although the input channel socket I have typically been using has started to get a bit intermittent). It has been interesting to watch what other interfaces have shown up at the low price end, and the Focusrite range appears to be ok as a replacement due to its high impedance single ended instrument input (as I typically use 10:1 scope probe connections for general bench work. Until both channels on the 0404 fail then I'm just happy to watch, but thanx for the offer.
Nostalgically I first heard Autobarn when it got released on 2JJ, which was a delight as it needed the ionosphere to assist with such long range reception.
Nostalgically I first heard Autobarn when it got released on 2JJ, which was a delight as it needed the ionosphere to assist with such long range reception.
the EMU performed (and sounded) great. I'm an import so only ever known it as triplej. I love Kraftwerk as does my 8yo. Still sounds futuristic and will for a long time.
Hi reddish, the Motu M2 turned up yesterday. After a bit of tweaking i got THD @ 0.00019 and THD+N @ 0.00097. I don't use REW so wont pollute the thread with another product's screen shots. You'll just have to believe me 🙂. The overall finish of the unit is better than I expected. It wasn't cheap but does seem a top performer. What it has shown me already is i need to upgrade my test leads! Never saw that with the 2i2 or EMU. Not sure why I got such mixed bag results with the 2i2 but I note xrk used an external osc. to get top results. I'd do the same.
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I've got hold of an M2 and I will be setting it up with rew over the next few days, but a question on the loop back and what resistance to enter into rew. Looking at the m2 datasheet it says impedence load for xlr at 2.65k, trs single ended 1meg and trs balanced at 2meg. This maybe a simple question, bit do I just choose the resistances mentioned for which connection I use?
No, REW just points to a particular 'input channel' on the interface. It will be up to you to connect your input signal to the interface in such a way as you present the signal with the appropriate balanced/unbalanced and impedance characteristics. I typically just use the unbalanced (SE) 1Meg input for quick benchwork with my EMU0404, as I always work through a standard 10:1 or 100:1 scope probe (to alleviate any chance of overloading an interface input, and causing damage). The only issue for scope probes is that there will likely be some inherent HF roll-off even after probe compensation, so a calibration file is then standard setup for a particular probe (I need a cal file anyway for my EMU as I often want to go down to 2Hz).
Hello,
Here are the REW calibration files of my Motu M2 that I'm using for the moment only to listen with headphones (sounds better than Yamaha Steinberg UR22mkII); but it can give you an idea of the quality of this soundcard.
Motu M2 performs and sounds great.
Here is a link to download the zip file:
WeTransfer
Hi, unsure if this is the best REW thread but anyway.
Someone using MAC (Big Sur) with REV?
Latest Beta is very unstable and the gui has some weird behaviour.
"Everything" works fine but when I am doing an RTA the looks of it is a bit strange.
No matter how I resize or try to change looks every "pushbuttons" on tom are almost completely hidden.
If I go into settings (upper right) and press for instance distortion settins, apperance or Trace options it freezes every time.
A big CPU hog is also present and have to kill the process.
Anyone else experienced this?
Tried restarting the machine but it does not help.
Someone using MAC (Big Sur) with REV?
Latest Beta is very unstable and the gui has some weird behaviour.
"Everything" works fine but when I am doing an RTA the looks of it is a bit strange.
No matter how I resize or try to change looks every "pushbuttons" on tom are almost completely hidden.
If I go into settings (upper right) and press for instance distortion settins, apperance or Trace options it freezes every time.
A big CPU hog is also present and have to kill the process.
Anyone else experienced this?
Tried restarting the machine but it does not help.
Attachments
Hi bambadoo. Updated my REW on MacBook Pro Big Sur 11.2 to the version V5.20 RC5.
Everything looks fine. No "effects" like in your pictures.
Everything looks fine. No "effects" like in your pictures.